Snooty, a legendary manatee known as the world’s oldest, has died in an apparent underwater accident at the Florida facility where he had lived since 1949, officials said Sunday.

Snooty's death came just a day after the official mascot of Manatee County, Fla., celebrated his 69th birthday with a cake made of fruit and vegetables. South Florida Museum officials tweeted that the two events "are unrelated.”

“Our initial investigation indicates that Snooty’s death was a heartbreaking accident and we’re all quite devastated about his passing,” Brynne Anne Besio, the museum’s CEO, said on the facility’s website.

Besio said the Bradenton, Fla., museum would conduct a full investigation.

Early indications showed that Snooty, who was found in an underwater area only used to access plumbing for his exhibit’s life support system, apparently swam through a panel door that is normally bolted shut. Somehow, Besio said, the door had been knocked loose.

She said Snooty’s habitat undergoes a daily visual inspection and that there were “no indications the previous day that there was anything amiss.”

The aquarium was closed Sunday while staff investigated and those who worked with Snooty had "an opportunity to grieve,” she wrote. The other three manatees undergoing rehabilitation in Snooty’s habitat were unharmed, Besio said.

A Baby Boomer, Snooty was born in 1948 at the Miami Aquarium and Tackle Company, the first recorded birth of a manatee in human care, the museum said. He relocated to Bradenton in 1949 and was known as “Baby Snoots.”

He became Manatee County’s official mascot in 1979.

Museum officials said an autopsy will be performed at the Florida Fish and Wildlife Conservation Commission’s Marine Mammal Pathobiology Laboratory in St. Petersburg.

The museum is asking fans to share personal memories of Snooty on its Facebook page